Demountable curtained grill for acoustic loudspeaker enclosure and the like



STIC

Dec 29, 1964 H. H. scoTT DEMOUNTABLE CURTAINED GRILL FOR Acou LOUDSPEAKER ENcLosuRE AND THE LIKE: Filed Nov. 12, 1963 INVENTOR HERMON H. SCOTT FIGZ United States Patent Oilice 3,163,254 Patented Dec. 29, 1964 3,163,254 DEMOUNTABLE CURTAHNED GRILL FOR ACOUSTIC LOUDSPEAKER ENCLOSURE AND THE LIKE Hormon H. Scott, Grasshopper Lane, Lincoln, Mass. Filed Nov. 12, 1963, Ser. No. 322,963 3 Claims. (Cl. 1mg-31) The present invention relates to demountable curtained grilles for covering acoustic loudspeaker enclosures and the like.

One of the problems that has long confronted the acoustic ant and, more particularly, that portion of the iield dealing with the manufacture of loudspeaker assemblies for use in homes and other locations where aesthetic properties are of prime commercial importance, has been the providing of a facing or cover for loudspeaker enclosures that presents an aesthetic, attractive appearance, while minimally interfering with the propagation of acoustic energy through the facing or covering. In the past, resort has been to frames carrying stretched, porous fabrics that may at least blend with the decor of a wide variety of differently furnished homes and other locations.`

Other proposals have involved perforated facings of other types that cover the loudspeakers. Doors have also been provided for hiding the covers when the apparatus is not in use. By and large, however, though the desirability of matching the appearance of loudspeaker covers to the specific decorations of the individual home or other location has been recognized and much sought after, the ait i has had to content itself with the above type of standard treatment.

In the sound-reproducing console field, particularly after the advent of stereophonic sound reproduction, requiring/the utilization of a pair of sizeable, spaced loudspeaker areas, this problem has become particularly important. The manufacture of such consoles, moreover, is such that the facing is general-ly fabricated as an integral part of the furniture, with the loudspeaker assemblies inserted or removed from the rear. This has further rendered it impractical for the user to try to remove a particular fabric or other perforated covering for the loudspeaker enclosure and replace it by a more appropriate material or to repair inadvertent tears or damage.

An object of the present invention, accordingly, is to provide a new and improved covering for an acoustic loudspeaker enclosure that shall not be subject to the above-described disadvantages but that, to the contrary, enables the ready matching of the texture and appearance of the loudspeaker cover to the individual decor of a home or other location, together with the feature of ready accessibility from the front of the cabinet, without tools, to enable change of decor or cleaning of the same at will, together with insurance against deleterious vibration, ilapping or other eects that might otherwise interfere with the proper operation of the acoustic system.

A further object is to provide a novel demountable cuntained grill for covering an acoustic loudspeaker enclosure and the like.

Other and further objects will be explained hereinafter and will be more particularly pointed out in connection with the appended claims. In summary, however, the invention contemplates a front grill that would normally be vibratory in response to acoustic energy directed thereupon and that is mounted to cover an aperture in a frame by resilient stripping means fitted about the .aperture and clamping the peripheral portions of the grill against the frame to damp vibrations of the grill that might otherwise be caused by acoustic energy directed thereupon. Curtain-supporting strips are carried by opposite rearsurface edge portions of the fname that are spaced from the frame, with acoustically transparent curtain material of any desired pattern, color, texture and the like interposed in the space between the strips and frame and hung tightly between the strips, preferably being pleated to avoid iiapping, the material also muffling possible vibrations of the strips. The grill-and-curtain-carrying frame is removably mounted from the front of the enclosure by means of cooperating projections and receptacles carried by the frame and enclosure for accurate positioning of the frame, so that its demountable nature is not detectable from the front, the projections being tightly fitted within the receptacles to prevent vibration of the frame in response to acoustic energy directed thereupon. Preferred constructional details are hereinafter set forth.

The invention will now be described in connection with the accompanying drawing, FIG. l of which is an isometric view illustrating the curtained grill of the present invention prior to assembly upon the front of a loudspeaker' enclosure; and

FIG. 2 is a front elevation of a modiiied grill structure.

Referring to the drawing, a loudspeaker enclosure is shown at 1, including7 for example, a conical bass speaker 3 and la tweeter array 3 mounted thereabove. The cover for the front opening Z of the enclosure 1 is constructed, in accordance with the present invention, in the form of a frame 5 having a central aperture 7', shown substantially rectangular in the embodiment of FIG.1, over which a grill, such as a crossed-mesh wire grill 9, is to be mounted. The grill 9 will, of course, be subjected to the pressure waves produced by the propagation of acoustic energy from the loudspeakers 3, 3 and will tend to vibrate in response to such acoustic energy directed thereupon, possibly introducing vibration, noise or rattle that is undesirable. This may be overcome by at least two techniques. First, if the crossed wires 9 themselves vibrate against one ano-ther in a deleterious manner, the wires may be of the lacquer pre-coated type that will reduce such vibrational noise. More important, the grill 9 is prevented from deleterious vibration by means of resilient stripping 11, as of rubber or the like, formed or fitted about the inner periphery of the aperture 7 and stapled or otherwise secured at 13 to clamp rlnly against the grill 9 and thus to damp vibrations of the grill caused by acoustic energy directed thereupon from the loudspeaker system 3, 3.

In order to provide the desired decor, a curtain 1S of substantially acoustically transparent material, which may be matched in color and pattern to the decor of any room or other location, is mounted behind the grill 9, stretched between a pair of curtain-supporting strips 17 that are mounted at the upper and lower edges of the rear surface of the frame 5, spaced from the frame 5 to receive the hem of the curtain material 15. In accordance with the invention, the curtain is relatively tightly stretched and held in place between the strips 17, and is preferably pleated, as shown, to obviate flapping thereof under the influence of the rather large-amplitude acoustic vibrations being directed thereupon by the closely` positioned loudspeaker system 3, 3.

The frame 5 carrying the grill 9 and curtain 15 is detachably mounted to cover the front opening 2 of the enclosure l by means of resilient projections 19, shown provided along the top edge of the rear surface of the frame 5, and peg projections 21, shown depending below the bottom of edge of the frame, respectively cooperating with resilient receptacles Ztl and aperture receptacles 22 disposed at the top and bottom edges of the opening 2 of the enclosure 1. Through the utilization of projections and receptacles that relatively tightly iit, vibration of the frame 5 in response to the acoustic energy directed thereupon from the loudspeaker system 3, 3' may be obviated,

a and the mounting of the frame S may be accurately located so as to conceal the fact that the frame is not an integral part of the front face of the cabinet or enclosure 1. A pair of longitudinal opposite side strips 23 may serve as stops against which the rear marginal surface of the frame will rest when the projections 19, shown as resilient V-shaped members, are received within, by forcing tightly in a horizontal direction into, the clamp receptacles and the lower projections 21 are received vertically Within the receptacles 22. The deniounting of the frame 5 from the front is readily effected by pulling out the top portion of the frame 5, as by inserting the fingers through the grill 9, and then lifting the frame 5 out of the receptacles 22. Thus, without having to go to the back of the cabinet and without having to remove the loudspeakers, as is presently required to try to place a different facing o-n current loudspeaker assemblies, or without having to use special tools for the removal of front faces, the user himself may remove the curtain-and-grill mounted frame 5, replace the curtain 15 to provide the desired decor, or replace it for cleaning, with simplicity and great flexibility, and with insurance that the acoustic performance of the enclosure is in no way impaired. In addition, as contrasted with the prior-art fabric facings and the like, the accidental insertion of objects through the grill 9 cannot usually seriously damage the cover; but if there is damage, the curtain 15 can be readily replaced without the major removal of equipment inherent in prior-art structures.

In the event that further vibration of the grill must be reduced, and/ or in the event that decorative strips or other patterns are desired to be superimposed upon the grill, further cross members secured to the frame over a portion of the aperture 7 thereof may be provided as -at 1', being used to hold further a vibration damping strip or strips 4 against the grill structure 9.

Further modifications will also occur to those skilled in `the art and all such are considered to fall within the spirit and scope of the invention as defined in the appended claims.

What is claimed is:

1. A demountable curtained grill for covering an opening in an acoustic loudspeaker enclosure and the like having, in combination, a grill for the said enclosure normally vibratory in response to acoustic energy directed thereupon, a frame provided with an aperture `in which the grill is mounted, resilient stripping means fitted about the aperture and clamping the peripheral portions of the grill against the frame to damp vibrations of the grill caused by acoustic energy directed thereupon, curtainsupporting strips carried by opposite rear-surface edge portions of the frame and spaced therefrom with substantially acoustically transparent curtain material interposed in the space between the strips and frame to muiiie vibrations of the strips, and mounting means comprising coperating projections and receptacles carried by the frame and the enclosure for accurately mounting and demounting the grill-and-curtain-carrying frame upon and from the said opening, respectively, the projections being tightly fitted within the receptacles to prevent vibration of the frame in response to acoustic energy directed thereupon.

2. A demountable curtained grill for covering an opening in an acoustic loudspeaker enclosure and the like having, in combination, a crossed wire-mesh grill for the, said enclosure normally vibratory in respone to acoustic energy directed thereupon, the Wire being coated to reduce Vibrational noise caused by the vibration of crossing wires, a frame provided with an aperture in which the grill is mounted, a resilient stripping means fitted about the aperture and clamping the peripheral portions of the grill against the frame to damp vibrations of the grill caused by acoustic energy directed thereupon, curtain-supporting strips carried by opposite rear-surface edge portions of the frame and spaced therefrom with substantially acoustically transparent curtain material interposed in the space between the strips and frame to muiiie Vibrations of the strips, the curtain material being held tightly between the strips and being pleated to obviate iapping thereof, and mounting means comprising cooperating projections and receptacles carried by the frame and the enclosure for accurately mounting yand demounting the grill-and-curtaincarrying frame upon and from the said opening, respectively, the projections being tightly fitted within the receptacles to prevent vibration of the frame in response to acoustic energy directed thereupon.

3. A demountable curtained gnill for covering an opening in an acoustic loudspeaker enclosure and the like having, in combination, a crossed wire-mesh grill for the said enclosure normally vibratory in response to acoustic energy directed thereupon, the Wire being coated to reduce vibrational noise caused by the vibration of crossing wires, a frame provided with an aperture in which the grill is mounted, resilient stripping means fitted about the aperture and clamping the peripheral portions of the grill against the frame to damp vibrations of the grill caused by acoustic energy directed thereupon, curtain-supporting strips carried by opposite rear-surface edge portions of the frame and spaced therefrom with substantially acoustically transparent curtain material interposed in the space between the strips and frame to muiie vibrations of the strips, the curtain material being held tightly between the strips and being pleated to obviate flapping thereof, and mounting means comprising cooperating projections and receptacles carried by the frame and the enclosure for accurately mounting and demounting the grill-and-curtaiincarrying frame upon and from the said opening, respectively, lthe projections being tightly fitted within the receptacles to prevent vibration of the frame in response to acoustic energy directed thereupon, and a further vibration-damping strip held against a predetermined front portion of the grill by a cross member secured to the frame over a portion of the aperture thereof.

References Cited bythe Examiner UNITED STATES PATENTS 2,447,576 8/48 Gustafson 312-7 2,913,067 11/59 Johnston ISI-31.1

FOREIGN PATENTS 813,451 ll/55 Great Britain.

LEYLAND M. MARTIN, Primary Examiner.

LEO SMILOW, Examiner. 

1. A DEMOUNTABLE CURTAINED GRILL FOR COVERING AN OPENING IN AN ACOUSTIC LOUDSPEAKER ENCLOSURE AND THE LIKE HAVING, IN COMBINATION, A GRILL FOR THE SAID ENCLOSURE NORMALLY VIBRATORY IN RESPONSE TO ACOUSTIC ENERGY DIRECTED THEREUPON, A FRAME PROVIDED WITH AN APERTURE IN WHICH THE GRILL IS MOUNTED, RESILIENT STRIPPING MEANS FITTED ABOUT THE APERTURE AND CLAMPING THE PERIPHERAL PORTIONS OF THE GRILL AGAINST THE FRAME TO DAMP VIBRATIONS OF THE GRILL CAUSED BY ACOUSTIC ENERGY DIRECTED THEREUPON, CURTAINSUPPORTING STRIPS CARRIED BY OPPOSITE REAR-SURFACE EDGE PORTIONS OF THE FRAME AND SPACED THEREFROM WITH SUBSTANTIALLY ACOUSTICALLY TRANSPARENT CURTAIN MATERIAL INTERPOSED IN THE SPACE BETWEEN THE STRIPS AND FRAME TO MUFFLE VIBRATIONS OF THE STRIPS, AND MOUNTING MEANS COMPRISING COPERATING PROJECTIONS AND RECEPTACLES CARRIED BY THE FRAME AND THE ENCLOSURE FOR ACCURATELY MOUNTING AND DEMOUNTING THE GRILL-AND-CURTAIN-CARRYING FRAME UPON AND FROM THE SAID OPENING, RESPECTIVELY, THE PROJECTIONS BEING TIGHTLY FITTED WITHIN THE RECEPTACLES TO PREVENT VIBRATION OF THE FRAME IN RESPONSE TO ACOUSTIC ENERGY DIRECTED THEREUPON. 